Hurricane Melissa strengthened into a Category 4 storm on Sunday, unleashing torrential rain and threatening to bring catastrophic flooding to the northern Caribbean.

Hurricane Melissa has strengthened into a major Category 4 hurricane, with the possibility of intensifying to a Category 5 storm Sunday night, unleashing torrential rain and threatening to cause catastrophic flooding in the northern Caribbean,

The NHC said strengthening is expected to continue, and the storm will likely become a catastrophic Category 5 hurricane as it creeps closer to Jamaica.

Melissa strengthened into a major hurricane and is expected to bring "catastrophic" flash flooding and landslides to Jamaica, Haiti and the Dominican Republic.

Hurricane Melissa has strengthened into a major Category 4 hurricane and could grow further. As much as 40 inches of rain are forecast in parts of the northern Caribbean.

EYE ON THE TROPICS  Life-threatening flooding, landslides and storm surge are expected in Jamaica and southern Hispaniola as Melissa continues to strengthen.

Hurricane Melissa strengthened into a Category 4 storm as it churned northwest through the Caribbean Sea on Sunday.

Melissa wasted no time harvesting a rich reservoir of warm water in the central Caribbean south of Jamaica on Saturday to intensify at an extreme rate – from a 70 mph tropical storm Saturday morning to a 140 mph Category 4 hurricane before sunrise Sunday.

Hurricane Melissa has strengthened into a hurricane and could soon rapidly intensify into a monstrous Category 4 or 5 storm.